Recoilless rifle with expanding nozzle



Aug. 16, 1960 A. BE NDITT ErAL 2,949,061

RECOILLESS RIFLE WITH EXPANDING NOZZLE Filed Aug; 3. 1959 INVENTORS' ALBERT BENDITT N g BY 0. WALTON MUSSER w v m ,X PM

2 Sheets-She et 1 s Q 9ZJ'VATTORNEIYSH' Aug. 16,1960 1 v A. BENDITT ETAL v 2, 6 v I RECOILLESS RIFLE WITH EXPANDING NOZZLE Ril'ed Aug; 5. 1959 i Y Y M V -2 Sheets-Sheet 2 KT 44 I INVENTORS' ALBERT BENDITT C. WALTON MUSSER ATTORNEYs United Sates Patent RECOILLESS RllFLE WITH EXPANDING NOZZLE Albert Benditt, Philadelphia, Pa., and C Walton Musser,

Beverly, Mass., assignors to the United States of America as represented by the Secretary of the Army Filed Aug. 3, 1959, Ser. No. 831,446 1 Claim. (Cl. 89-1.7)

(Granted under Title 35, US. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to us of any royalty thereon.

This invention relates to a recoilless rifle with an expanding nozzle, and more particularly to an improvement on the gun disclosed in a copending application of C Walton Musser, Serial No. 634,128, filed January 14, 1957 for Recoilless Gun Having Radially Movable Breech Sectors, now Patent 2,874,614, this copending application being a division of application Serial No. 271,056, filed February 11, 1952, for Recoilless Type Ammunition Having Self Contained Venturi, now Patent 2,791,961.

In accordance with the aforesaid divisional application, a plurality of radially movable sectors are operated by means of a rotatable cap to define a venturi and encircle a similarly shaped portion of the ammunition. The present invention obviates the need of this rotatable cap by the provision of a plurality of sectors which are (1) movable axially and radially to pass the ammunition round into the chamber and (2) function automatically to lock the round in place. This makes possible a reduction in the weight of a 90 mm. gun from about forty pounds to twenty-eight pounds, thus giving the infantryman a larger caliber shoulder-fired rifle than he could carry heretofore. As will appear this improved gun is adapted to be utilized with the cartridge having a combustible or frangible powder envelope. When so utilized, there is no cartridge casing to extract and a new round can be inserted immediately following the firing of a previous round.

The invention will be better understood from the following description when considered in connection with the accompanying drawings and its scope is indicated by the appended claims.

Referring to the drawings:

Fig. 1 illustrates, partly in section, a preferred form of the invention,

Fig. 2 is a rear end view of the gun and projectile,

Fig. 3 indicates the different positions assumed by the sectors of the expandable nozzle, and

Fig. 4 illustrates a preferred form of spring for biasing the nozzle sectors to a position where they lock the cartridge in the gun.

The gun of Figs. 1 and 2 includes a barrel 10, a chamber 11 and a nozzle which includes a plurality of segments 12. These segments have near their rear ends a groove 13 (see Figs. 1 and 3) which is engaged by the inwardly bent ends 14 (see Fig. 4) of a spring 15 which surrounds and supports the nozzle segments 12.

The spring 15 is made of one piece, has at its forward end a band 16 and at its rear end a band 17 from which there extends a plurality of projections each bent inwardly as indicated to the groove at the rear of the segments 12 and each having a tang 19 which rides in a groove 25 on the inner surface of the rearward extension of the chamber 11. Between the band-s 16 and 17 are a plurality of helical springs 20, one for each sector 12 of the nozzle.

One of the most novel characteristics of this nozzle arrangement is the means by which the segments are prevented from cocking as they are moved axially in the rifle. Since these segments are actually discrete particles and separated from each other, they could move somewhat independently of each other so that they bind in the rear extension. When the rifle was first made, this problem was discovered, and a unique method was utilized to prevent this from occurring.

Whenever it is desired to slide an object within a cylinder, it is mandatory that the object that is being slid must have a length sufliciently great to prevent it from cocking and binding. This has been a common problem in engineering for years. Usually, the only recourse is to make the object longer or to put some extension on this object that will permit it to be guided. Neither of these means could be used for the subject noz-zle.

To overcome this difliculty, the rear end of the rifle extension has rifling grooves 25 put in at a 45 angle. Cooperating with these grooves are the tangs 19. These tangs, having a set distance apart, will then, of necessity, make that the entire assembly must move forward at all times with the rear surface perpendicular to the bore axis.

As previously indicated, the spring 15 surrounds and supports the segments 12. In the extended position of this spring, the segments 12 are forced together in position indicated by the full line of Fig. 3. When a cartridge 21 is forced into the chamber 11, the nozzle expands, the segments 12 assuming the position indicated by the broken line of Fig. 3. Seating of the cartridge in the chamber releases the segments so that they are forced rearwardly by the spring until their sloped forward portions 23 engage the rear wall 24 of the chamber 11. In this position, they lock the cartridge 21 in place.

The cartridge 21, as indicated above, is of the type having a case which is consumed by the firing of the cartridge. It is illustrated as having an explosively fired primer 22 but obviously is usable with other types of primer.

The above-described spring 15 is disclosed and claimed in a copending application of Andrew J. Grandy and Charles A. Greenwood, Ser. No. 845,294, filed October 8, 1959, for Multi-Lead, Stub Helical Spring.

We claim:

A recoilless rifle including a chamber having a rear extension with internal longitudinal grooves near its rear end, a plurality of nozzle forming segments within said extension and each having an external groove near its rear end, and a one-piece resilient member resting at one end against an outer surface of said chamber and having at the other end a plurality of tangs each in a different one of said longitudinal grooves and a plurality of inwardly bent ends each in a different one of said external grooves whereby said segments are expanded upon the insertion of a cartridge into said chamber and are automatically retracted by said resilient member to lock said cartridge in said chamber and to form a nozzle at the rear thereof.

References Cited in the file of this patent UNITED STATES PATENTS 2,874,614 Musser Feb. 24, 1959 

